GCSE Biology - Food Tests Practicals (2027/28 exams)
Cognito
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GCSE Biology - Food Tests Practicals (2027/28 exams)
283 332 просмотра · 1 год назад
Cognito
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283 332 просмотра · 1 год назад
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** WHAT'S COVERED **
1. Preparing a food sample for testing
Grinding the food
Dissolving in distilled water
Filtering the solution
2. Benedict's test for sugars
Testing for reducing sugars
Using a water bath
Observing colour changes (blue to green/yellow/brick-red)
3. Iodine test for starch
Adding iodine solution
Observing colour change (browny-orange to blue-black)
4. Biuret test for proteins
Adding Biuret solution (or potassium hydroxide and copper sulfate for Edexcel)
Observing colour change (blue to pink/purple)
5. Sudan III test for lipids
Adding Sudan III stain solution
Observing the formation of a red-stained top layer
6. Emulsion test for lipids (Edexcel specific)
Adding ethanol and shaking
Adding distilled water
Observing a cloudy white colour (emulsion)
** CHAPTERS **
0:00 Introduction to Food Tests
0:36 Preparing a Food Sample
1:12 Benedict's Test (Sugars)
2:17 Iodine Test (Starch)
2:56 Biuret Test (Proteins)
3:34 Sudan III Test (Lipids)
4:07 Emulsion Test (Lipids - Edexcel)
** PLAYLISTS **
• GCSE Maths (9-1)
• GCSE Biology (9-1)
• GCSE Chemistry (9-1)
• GCSE Physics (9-1)
• A-Level Biology
#GCSE #Biology #study